1. Field of the Invention
The invention relates to a mobile computer with a desktop type processor; in particular, to a mobile computer in which battery life is maintained by a power management method.
2. Description of the Related Art
The difference between a processor for a mobile computer and a desktop type processor is that the former is a chip designed based on the requirements of a mobile computer. Specifically, since the space inside the mobile computer is small, heat-dissipation is limited. Additionally, battery life is also limited. Thus, processor size and power consumption place severe limitations on mobile computer designs. As a result, the wafer for manufacturing the processor for the mobile computer must be tested and conform to more strict specifications. Furthermore, the most advanced circuit technology is applied to mobile computer processors in order to achieve performance comparable to a desktop type processor. In addition, the processor for the mobile computer is typically driven by a lower operation voltage. Thus, waste heat and power consumption are lower than in a desktop computer.
Furthermore, mobile computer processors with clock speed equal to their desktop counterparts are more expensive. Specifically, the difference in price between a mobile processor and a desktop processor is around 200–500 dollars. Due to this price difference, several manufacturers have replaced mobile processors with desktop processors in mobile computers. Thus, reducing the overall cost of the mobile computer.
Referring to FIG. 1, in the conventional mobile computer 10 with a desktop type processor, an external battery 11 supplies power to the mobile computer by an inner system power supply 12. The inner system power supply 12 powers the clock generator 13, a desktop type processor 14, a chipset 15, and a memory 16. It is noted that the clock generator 13 outputs a clock signal to the desktop type processor 14, the chipset 15, and the memory 16 so as to provide operational frequencies required by the desktop type processor 14, the chipset 15, and the memory 16.
When a large amount of the data is calculated by the desktop type processor 14, the amount of current required by the desktop type processor 14 increases correspondingly. At this time, the amount of the current supplied by the battery 11 may exceed the maximum amount of the current that the battery 11 can supply. Thus, the life of the battery 11 may decrease.
To extend the life of the battery 11, a switch is additionally disposed in the conventional mobile computer with the desktop type processor. When the amount of the current supplied by the battery exceeds a maximum level, a circuit in the mobile computer is automatically turned off by the switch. Thus, the amount of the current supplied by the battery is prevented from exceeding its maximum level
Although the lifetime of the battery can be properly maintained by the above manner, it is inconvenient for the user. Specifically, since the circuit is directly turned off by the switch, the mobile computer may be shut down accidentally.